Means for safeguarding closed vessels against fire and explosion.



I P. GUNGERICH. MEANS FOR SAFEGUARDING CLOSED VESSELS AGAINST FIRE ANDEXPLOSION.

APPLICATION FILED MAR. 26. I913.

o Patented Feb. 22, 1916.

3 SHEETS-SHEET I.

I I l I I I MM 21a] Gingerz'cfa 7 474 P. GUNGERICH. MEANS FORSAFEGUARDING CLOSED VESSELS AGAINST FIRE AND EXPLOSION. APPLICATIONFILED MAR. 26, I913.

1,17%,8846 Patented Feb. 22,1916.

3 SHEETS-SHEET 2- P. GUNGERICH. MEANS FOR SAFEGUARDING CLOSED VESSELSAGAINST FIRE AND EXPLOSION.

APPLICATION FILED MAR. 26, I913.

Patented Feb. 22, 1916.

3 SHEETS-SHEET 3- I I l l l i I are,

PAU L GIINGERICH, OF BERLIN-STEGLITZ, GERMANY, ASSIGNOR TO MiAR'IINI &I-I'U'NEKE MASCHINENBAU-AKTIEN-GESELLSCI-IAFT, 01E BERLIN, GERMANY,

.A CORPORATION OF GERMANY.

Specification of Letters Patent.

Patented Feb. 22, 1916.

Application filed March 26, 1913. Serial No. 757,037.

To all whom it may concern.

Be it known that I, PAUL Gr'iivonuien, a citizen of the German Empire,and resident of Berlin-Steglitz, Germany, have invented certain new anduseful Improvement in Means for Safeguarding Closed Vessels Against Fireand Explosion, of which the following is a specification.

This invention relates to means for safeguarding against fire andexplosion, closed vessels in which materials or articles are treatedwith inflammable liquids in the presence of a protective gas. Instancesof. such treatment will .be found in the chemical cleaning of clothingetc. by means of washing machines using benzin (gasolene), and in theremoval of fats from bones,

leather and the like in extraction apparatus using volatile solvents.

To prevent explosions in industrial processes carried out withinflammable liquids, in closed vessels, it has been proposed tointroduce a non-oxidizable or inert protective ga (such as carbonic acidgas or nitrogen) into the vessel, thus preventing the vapors of theinflammable liquid from forming an explosive mixture with the aircontained in the vessel in which the operation is conducted. The safetyagainst explosion within the vessel depends on the presence of awell-determined amount of protective gas, sufficient to keep theproportions of the resulting mixture of gases belowthe danger point orexplosion point of the particular mixture, the explosion points ofvarious gase or gas mixtures being well known. Therefore, all danger ofan explosion withv in the vessel may be avoided by' not intro- Thepresent invention is based on the considera-tion that whenever two gases(in the present case, air and protective gas) one of which is under apressure different from the other, are mixed in diflerent proporzin, andsoiled benzin respectively.

tions, there will correspond to each particular miXture-prop0rtion,apredetermined pressure prevailing in the vessel and susceptible of beingutilized for the purpose of governing a locking device adapted to closea shut-off device provided in the conduit through which the inflammableliquid is supplied to the vessel. This device will remain closed, thuspreventing the admission of said liquid to the vessel, until the air orthe mixture of the air with the protec-' tive gas added thereto, has apredetermined pressure which will insure the n0n-explosiveness of themixture formed subsequently when vapors are evolved from the inflammableliquid. The pressure which governs the locking device and the release ofthe shut-0H" device located in the conduit through which the inflammableliquid is supplied, may be obtained either by introducing the protectivegas under apressure greater than atmospheric pressure into the vesselfilled with air under atmospheric pressure, or by first'producing apartial vacuum in the vessel by means of a suitable exhausting device,and then utilizing this vacuum for the introduction of an amount ofprotective gas sufficient to prevent the formation of explosive mixture.In this latter case the protectivegas need not be under a pressurehigher than atmospheric pressure.

It may be desirable to provide additional means for insuring the propersupply and withdrawal of the protective gas and of the inflammableliquid, particularly if, (as in chemical washing or cleaning) separatevessels are used for pure benzin, semi-pure ben- For this purpose theshutoff devices for the protective gas and for the inflammable liquidrespectively may be connected positively or operativelv in such a mannerthat the opening and closing of these devices canbe effected only in theproper order. In a handactuated apparatus, this is preferablyaccomplished by positively connecting the shut-off device or devices forthe supply and withdrawal of protective gas, and the shutoff device ordevices for the admission of the inflammable liquid, with a crankcontrolled by the locking device governed by the pressure prevailingwithin the vessel.

Several examples of apparatus suitable.

for carrying out the process described above,

are shown in the accompanying drawings, in

which A Figure 1 1s a diagrammatic elevation (partly in section) of aplant for chemical washing or cleaning, with a locking device governedby a pressure above atmospheric pressure, prevailing in the washingmaelevation of the construction shown in Fig."

2, with parts in section; Fig. 4 is a section taken on line A,-B ofFig.2; Figs. 5 and 6 are top views showing the valves forshutting off thesupply of the inflammable l quid, and also showing their latching devicein two different positions; Figs. 7 and 8 are vertical sectionsrepresenting two additional forms of construction of the locking devicegoverned by a pressure above atmospheric pressure, prevailing in thewash ng machine; and Fig. 9 is a diagrammatic elevation (partly insection), of a plant for chemical washing or cleaning, with a lockingdevice governed by a partial vacuum in the washing machine.

In the construction illustrated by Fig. 1,

" the receptacle in which the clothing or other articles to be cleanedare treated with a volatile solvent, for instance benzin, consists of avessel 2 having a lateral door'l adapted to close gas-tight, said vesselcontaining theusual'perforated drum (not shown) which is rotated bymeans of a belt (not shown) susceptible of being applied either to thefast pulley3 or to the loose pulley 4 on the projecting end of the drumshaft. In this example of the invention, the benzin is used over andover again for cleaning purposes,

such procedure being well known. For this purpose, three, receptaclesare provided, to wit a pure benzin receptacle 5, the benzin of which isused only for rinsing the cleaned articles, a semipure benzin,receptacle. 6, the benzin of. which is used for washing the goods withthe aid of the perforated drum in the vessel 2, and a soiled benzinreceptacle '7, the benzin of which is purified by distillation so as tobe available for further use.

The benzin is stored in these receptacles 5, 6 and 7 under conditionssafeguarding against explosions, the upper portions of the receptaclesbeing filled with a non-oxidizable protective gas, such as carbonic acidgas or nitrcgen. The receptacles 5 and 6 are connected by pipes 8 and 9respectively with a tank (not shown) in which the protective gas iscontained under a pressure suflicient to drive the pure benzin into thevessel 2 through a pipe 10 and the semipure benzin into said vesselthrough a pipe 11. In the pipe 9 for the supply of the protective gas isarranged a shut-off device or cook 12, while the pipes 10 and 11 areprovided with shutoff devices or valves 13 and 14 respectively,controlling the connection of the rece 'itacles 5 and Orespectively withthe washing'vessel or machine 2. The soiled benzin receptacle 7 issupplied with, protective gas through a pipe 15 connected with agasometer 16 having a bell 17 adapted to move up and down. Thisgasometer is filled with a protective gas which is also adapted to beused for safeguarding the washingmachine or vessel 2'against explosion.Protective'gas underpressure above atmospheric pressure is supplied tothe, washing machine or vessel 2 through a pipe-18 branched off from thepipe 9 and provided with a shut-off device or cook 19, said pipe 18leading to the top or cover of the vessel 2. This vessel is further incommunication with. a pipe 20,

which according to the position of a threeway shut-oil device or cock 21can be connected'either with a pipe 22 branched oil" from the pipe 15orwith'the interior of a casing 23. The casing 23-is provided with ayielding pressure member which in the construction illustrated byFig. 1. consists of two valve disks 25 and 26 secured to a valve rod 24,one o-rthe other of said disks being adapted to close the valve openingor passage 27. Onthe side nearest the disk 25 the passage 27 isconnected with a pipe 28 branched off from the pipe 22. The pressuremember'25, 26 is weighted by means of a weight 29 connected with the rod24, the lower end of said rod being adapted to enter a bore of the plugof the cock 21, so as to lock said cock. Thewashing machine or vesse12is further connected with thesurrounding'air by means of a pipe 31provided with a shut-ofl cock 30, and still another connection34,-provided with a shut-off cock 33. leads from the vessel 2 to anexhausting device or air pump 32. 'After having been used inthe vessel2, the pure benzin may be conveyed to the semi-pure benzin receptacle '6througha'pipe 36 provided with a stop cock 35. Similarly the semipurebenzin.

after use in the vessel 2, may be conveyed into the soiled-benzinreceptacle 7 through a pipe 38 provided with a shut-ofl' device 37 Thepipes 36 and 38 are branched ofi from a common pipe 39 connected withthe bottom of the vessel 2. The.cock 21, which is adapted to be lockedby the pressure member 25,

the crank shaft 42 supported in bearings 41. One face of the disk 43 isprovided with a cam groove 45 into which extends a crank pin 46 securedto the plug of the cock 21. The other face of the disk 43 has a camgroove 47 into which extends a crank pin 48 secured to the plug of thecock 19. The disk 44 is provided with a cam groove 49 (Fig. 4) intowhich extends the crank pin 50 secured to the cook 12. To the plug ofthe cook 21 is further secured a crank 51, connected by a link rod 52with a crank 53 of a horizontal shaft 54 journaled adjacent to thevalves 13 and 14. The rotation of theshaft 54 is transmitted, by meansof meshing bevel gears 55, 56, with an upright shaft 57, held againstlongitudinal movement and provided with a locking member 58 which "inthe closed position of the valves (Figs. 2 and 5) lies against stopdisks 61 and 62 provided on thevalve spindles 59 and 60 respectively;the valves are thus prevented from opening. The shape of the cam grooves45,

47, 49 and the connections for transmitting motion from the cock 21 tothe member 58 which looks the valves 13 and 14, are so selected that theopening and closing of the cocks 21, 19, 12, or the unlocking of thevalves 13 and 14 by turning the crank 40 will take place in the mannerrequired for .a safe operation, when the cook 21 establishescommunication between the pipe 20 (and therefore the interior of thewashing machine or vessel 2) and the casing 23. By, means of a suitablepawl or equivalent device (not shown) the crank 40 is held againstturning in one direction.

The weighting of the pressure member 25, 26 is so selected that theexistence of a predetermined degree of. pressure (above atmosphericpressure) in the vessel 2 will cause the said member to be raised to theposition indicated by dotted lines in Fig. 1, so that the lower disk orplate 26 will close the opening or passage 27, and so that the cock 21will be unlocked or released by the lifting of the rod 24.

The above-described device operates as follows: With the cock 21 in thelocked position as shown in Fig. 1, the cock 12 controlling the supplyof protective gas to the semipure benzin receptacle 6 is open, while thecook 19 controlling the supply of protective gas to the washing machineor vessel 2 and all the other cocks are closed and the valves 13,14 arelocked in their closed position. By then turning the crank 40 in thedirection of the arrow, through an angle of 90, the crank pin 48 isturned to the same extent and opens the cook 19, while the crank pins 46and 50 remain stationary owing to the concentric curvature of thecorresponding portions of the cam grooves 45 and 49 respectively, sothat the locking member 58 of the valves 13 and 14 also remainsstationary in its locking poistion. Protective gas under pressure willthen flow into the washing vessel 2 and will get mixed with the airconfined in said vessel or machine. As soon as the pressure of the gasmixture reaches a value corresponding to the weight bearing on thepressure member 25, 26, the latter and its rod 24 are raised, releasingthe cock 21. The parts are so proportionedthat the member 25, 26, willbe-raised only by such a pressure as will insure a non-explosivecharacter of the mixture formed upon the subsequent evolution ofgasolene or benzin vapors. Therefore, after the cook 21 has beenreleased as described, benzin may be introduced into the washing machineor vessel 2 without any danger of an explosion. This introduction ofbenzin is eflected by giving another quarter-turn to the crank 40, thatis to say, to a position 180 from its original position, whereby thecock 21 is turned to a position in which it places the pipe 20 in directcommunication with the pipe 22. As the crank 40 is thus turned, thecrank 48 is turned'also, to close the cook 19, while at the same timethe turning of the crank pins 51 and 53 will bring the locking member 58of the valves 13 and 14 into the releasing position shown in Fig. 6. Theopening of the cock 21 causes a certain quantity of protective gas toescape from the vessel 2 through the pipes 20, 22 and 15 into thegasometer 16, and into the outer air when the bell 17 is in its upperposition. This escape of gas reduces the pressure within-the vessel 2,and in the particular construction shown, the protective gas under thisreduced pressure, is utilized for preventing explosions in the soiledbenzin receptacle 7, the cover of which is connected with a branch orend of the pipe 15.

The valves 13 and 14 having been released, the valve 14 may be opened.The amount of semipure benzin required for the cleaning operation isforced into the washing machine or vessel 2 by the pressure of theprotective gas supplied to the receptacle 6 through the pipe 9; thevalve 14 is then closed manually, its stop disk 62 again coming to lieunder the locking member 58.

When the Washing operation has been completed, the cook 37 is opened toallow the soiled benzin to pass from the washing machine 2' to thesoiled benzin receptacle 7. The cock 37 is then closed again, and thevalve 13 opened, so that the protective gas passing from the pipe 8 intothe receptacle 5 will drive a certain quantity of pure benzin from thisreceptacle into the washing machine 2, through the pipe 10. If the valve13 is then closed, its stop disk 61 will also be brought back to lieunder the locking member 58.

After the rinsing operation, the pure benzin used for rinsing must beconveyed into the scmipure benzin receptacle 6. Since the protective gasin this receptacle is under a higher pressure than in the washingmachine 2. it would apparently be necessary to place the receptacle 6 ata level sufliciently below that of the washing machine to enable thispressure difference to be overcome by the head. In order to avoid theconsiderable height of the plant which such an arrangement wouldrequire, means are provided for equalizing the pressure in thesemipurebenzin receptacle 6 and the washing machine 2. This isaccomplished by giving the crank 40 a further quarter-turn (that is tosay, to a position 270 from the original position); the crank pin isthus turned downward to close the crck 12, while the crank 48 is turnedup to open the cook 19. Pressure in 6 and 2 will then become equalizedthrough the connections afforded by the pipes 9 and 18, so that uponopening the cock 35 benzin may flow from the washing machine 2 to thereceptacle 6 through the pipes 39 and 36. 'lhereupon the cook 35 isclosed again.

By turning the crank 40 through an angle of 270", the cock 21 is broughtback to its original position, in which a bore of the plug alines withthe rod 24' of the pressure member 25, 26. member 58 assumes again theposition shown in Fig. 5, in which it secures the two valves 13 and 14in their closed position. By again turning the crank 40 another 90 (thatis,

to the 360 position), the crank pin 48 is swung downward to again closethe cook 19 and the crank pin 50 is swung upward to again open the cook12.

The cleaned articles contained in the washing machine 2 may then bedried in suitable apparatus (not shown) provided for this purpose; thebenzin which adheres to these articles evaporates during this dryingoperation and may be recovered. in a condenser.. In order to avoidexposing the workmen to" the unpleasant vapors which may escape from theapparatus'upon opening the door 1, it may be advisable (before the dooris opened to remove the cleaned arqticles from the machine 2) towithdraw the larger portion of the mixture or vapors from tiles-washingmachine, 2; this may be ef-.

fected by first opening the cock 33 and then operating the air pump 32-to withdraw the gaseous mixture from the washing machine through thepipe 34 and forcing said mixture OlltlIltOl the surrounding air, thecook 30 being opened thereupon to admit air to 'the washing machine.

At this time the locking in communicating tubes 63, 64, one of which 63,is connected with the pipe 20 leading to the washing machine 2, whiletheother tube, 64, is enlarged at its upper end to form a float chamber 65,the lever of the liquid being in said chamber. At the top of the chamberis an opening or nipple 66 which according to the position of the cook67 is connected either with the pipe 20 or with the pipe 22 leading tothe gaso-meter 16. Before the washing machine 2 is operated, the chamber65 communicates with the pipe 22, as shown in Fig. 7, that is to say,one bore of the plug of the cock is open to the chamber 65. Into thisbore is adapted to project a locking rod 67 pivotally connected with onearm of a lever 68 fulcrumed within the casing or chamber 65, the otherarm of said lever carrying a float 69. If the pressure in the washingmachine 2 is the same as that of the surrounding air, the level of theliquid in the chamber 65 will be so low as to cause the rod 67 to enterthe bore of the plug and thus lock the cook 21. When upon opening thecook 19, pressure rises in the pipe 20, owing to the inflow ofprotective gas under pressure into the washing machine 2, the level ofthe liquid will sink in the tube 63 and rise in the chamber 65, thuscausing the float 69 to move upward, so as to withdraw the locking rod67 from the plug of the cook 21. The surface areas of the liquid in thetube 63 and chamber 65- respectively are so proportioned that the float69 will not reach the position in which it releases the cook 21, untilthe gas and air mixture in the washing machine has reached the properpressure assuring safety. After being released, the

cock '21 can'be turned so as to enable the cleaning operation to becarried out in the manner described above.

As shown in Fig. 8, the yielding pressure member serving to control thelocking member maybe constructed as a diaphragm 70 provided with a rod71 adapted to enter the bore of the cock plug. The "diaphragm7O issecured withina casing 72, the compart-' ment above the diaphragmcommunicating with the surrounding a1r through a nipple 73, while thecompartment below the diaphragm is connected with the pipe 20 by meansof the cock 21, before the operation of the washing machine 2 isstarted. A

weight 74 presses the diaphragm 70 downward, causing the rod 71 toremain in the bore of the cock plug until pressure Within the washingmachine has reached the proper. degree assuring safety, when the. rod 71will have been lifted out of the plug so as to release the cook 21.

In the construction represented in Fig. 9, the release of the valves 13and 14 controlling the supply of benzin, is made devantage that theprotective gas to be introfied by connecting, with the pipe leading tothe gasometer 16 and to the soiled benzin receptacle 7, a pipe 75 forsupplyin protective gas under a pressure but slightly above atmosphericpressure; furthermore,

the cock 76 controlled by the yielding pres- Slll'Br member 25, 26 will(in the locked position shown) connect the interior of the casing 23with the pipe 77 communicating with the pipe 15. The protective gas(under a relatively low pressure) will therefore enter the casin 23 andreach the lower face of the valve disk 25 or 26, whichever happens to beseated at the time. The other face of the said seated valve disk isexposed to the pressure prevailing in the washing machine 2, which isconnected with the upper end of the casing 23 by a pipe 78. From thelatter a pipe 79 leads to the cock 76 and can be connected with ordisconnected from the pipe 77 by turning said cock.

A cock 80 .is provided in the pipe 9 serving to supply the protectivegas under a relatively high pressure to the semipure benzin receptacle6. By a proper operation ofthis cock the supply of gas to the receptacle6 may be interrupted and this receptacle at the same time placed incommunication with a pipe 81 branched off from the pipe 18 which leadsto the washing machine. As in the construction shown in Figs. 1 to 6,the cock 76 may be connected by the cranks 5'1 and 53 with the lockingmember 58 of the valves 13 and 14, and with the hand crank 40 by a crankpin projecting into a cam groove 82 of a disk secured to the shaft 42 ofsaid hand crank. The shaft 42 also carries a disk provided with a camgroove 83 controlling the position of the cock 80. The mechanismoperated by the hand crank 40 further controls the Vent cook 30, aneccentric pin on the plug of said cock extending into the cam groove 84of a disk mounted on the shaft 42.

The operation of this form of the invention is as follows: After fillingthe washing machine 2 with the articles to be cleaned, and closing thedoor 1, the cock 33 is opened and a vacuum of a predetermined degree isproduced in the washing machine by means of the air pump 32. The properdegree of vacuum is found by calculation in each individual case. thecondition being that upon introducing the protective gas into themachine 2, this gas together with the air still contained in the machinewill form a mixture which will not be explosive after it has received,as a further constituent, the benzin vapors arising during the cleaningprocess.

As soon as this degree of vacuum is attalned in the washing machine 2(the vacuum extending through the pipe 78 as far as the valve disk 25),the pressure member 25, 26 is raised so that the disk 26 will close thecommunication of the casing with the pipe 78, the rod 24 being at the gsametime withdrawn from the bore of the cock 76; By turning the crank 40through 90 in the direction indicated by the arrow the cook 76 isbrought to a position in which the pipe 77 connected with the supply ofprotective gas, communicates with the pipe 79. A certain amount of theprotective gas, under a relatively low pressure, will then enter thewashing machine 2. During this operation of the crank 40, the cooks 80and 3.0 remain in the operative positions shown, being in operativerelation at the time with the concentric portions of the cam grooves 83and 84 respectively. At the same time the turning of the cock 76 willalso release the valves 13 and 14, so that by opening the valve 14semipure benzin may be admitted to the washing machine 2, the valvebeing then closed to allow the cleaning operation to be carried out insaid machine.

After the spent or soiled benzin has been drawn off into the soiledbenzin receptacle 7 and after a predetermined amount'of pure benzin fromthe receptacle 5 has been introduced into the washing machine 2 byopening and then closing the valve 13, this pure benzin, used forrinsing, must be transferred to the receptacle 6. Since in this latterthe prevailing pressure is the relatively high pressure of theprotective gas serving to convey the benzin, while the gas mixture inthe washing machine 2 is under a relatively lower pressure of theprotective gas, it IS necessary, as in the construction shown in Fig. 1,to equalize the pressures in the receptacle 6 and the machine 2. This isaccomplished by turning the crank 40 through an angle of 90, that is tosay, to the 180 position, whereby the cook 80 is brought to a positionin which the pipe 9 connected with the receptacle 6 communicates withthe pipe 81. The cock 30 however remains in its closed position,notwithstanding this oper-' ation of the crank 40, while the cook 76returns to its original position and is locked. At the same time thevalves 13 and 14 are also locked in their closed position.

Before opening the door 1, the gas mixture contained in the washingmachine 2 is withdrawn by means of the air pump32 and the crank 40 isgiven another quarter-turn (to the 270 position), thus bringing the cook80 back to its initial position and opening the cock 30. Only then canair enter the machine 2. Therefore, the positive connection of the cock30 with the crank 40 absolutely prevents any admission of air to thewashing machine by an accidental openlng of said cock, as long as avacuum exlsts 1n said machine; such accidental admission of air would ofcourse be liable to alter the' proportion of .the gaseous mixturecontained in the machine, and thus to defeat the purpose of thisinvention. Upon giving the crank 40 another quarter-turn, that is tosay, to its original position, no action takes place except the closingof the cook 30.

It will be evident that the constructions of the yielding pressuremember controlled by the pressure prevailing in the washing machinewhich are illustrated by Figs. 7 and 8, may also be used in connectionwith the plan shown in Fig. 9. If desired, the shutfor conveying aninflammable liquid to said vessel, a shut-off device controlling saidconduit, a device for locking in its closed position the shut-off devicewhich controls the flow through said conduit, and a pressure memberoperatively connected with said locking device and having a connectionwhereby it is exposed to the pressure prevailing within said vessel, sothat the shutoff device will be unlocked when the pressure in saidvessel attains a predetermined value.

2. The combination, with a vessel having means whereby it may be closedto the surrounding air or thrown open, of a conduit for conveying aninflammable liquid to said vessel, a shut-off device controlling saidconduit, a pressure member under the influence of the pressureprevailing in said vessel, and means controlled by said member forholding said shut-off device in its closed position until the pressurein said vessel attains a predetermined value.

3. The combination, with a vessel having means whereby it may be closedto the surrounding air or thrown open, of a device for exhausting gasfrom said vessel, a connection for supplying protective gas to saidvessel, a shut-off device controlling said connection, a device forlocking said shutofi device in its closed position, and a pressuremember connected with said locking device and having a connectionwhereby it is exposed to the pressure prevailing within member connectedwith said locking device and having a connection whereby it is exposedto the pressure of protective gas supplied at a pressure aboveatmospheric pressure.

5. The combination, with a vessel having means whereby it may be closedto the surrounding air or thrown open, of a connec tion for supplyingprotective gas to said vessel, a shut-ofl 'device controlling saidconnection, a device for locking. said shutoff device, a pressure membergoverning the position of said locking device, additional shut-offdevices controlling the flow of protective gas, a hand crank rotatablein one direction only, and operative connections between said crank andsaid shut-off devices to cause the latter to be opened and closed in theproper succession.

6. The combination, with a vessel having means whereby it may be closedto the surrounding air or thrown open, of receptacles adapted to containpure benzin and semipure benzin respectively, a connection from the gasspace of the semipure benzin receptacle to the gas space of said vessel,a shut-ofl' device in said connection, another connection for supplyingprotective gas to said vessel, another shut-ofl" device controlling saidlast-named connection, a device for locking the last-named shut-01fdevice, a pressure member controlling the position of said lockingdevice, and an operative connection between said shut-ofl devices tocontrol the temporary equalization of pressures in the said vessel andin the semipure benzin receptacle.

7. The combination, with a vessel having means whereby it may be closedto the surrounding air or'thrown open, of an exhausting device connectedwith said vessel, a shut-off device for controlling the connection ofsaid vessel with the surrounding air, means for locking said shut-offdevice, a connection for suppying protective gas to said vessel, ashut-ofl' device controlling said connection, a locking member for saidshutofl device, a pressure member connected with said locking member andhaving a connection whereby it is exposed to the reduced pressureprevailing within said vessel, and an operative connection between saidshut-ofi' devices, whereby the connection of said vessel with thesurrounding air cannot be established as long as a vacuum is maintainedin said vessel.

8. The combination, with a vessel having means whereby it may be closedto the surrounding air orthrown open, of a connection for supplying aliquid thereto, another connection for supplying protective gas to saidvessel, shut-off devices in said connections, a device for locking inits .closed position the device controlling the supply of liquid to saidvessel, and means governed by the pressure within the vessel, forreleasing said shut-off device from its locking device after theadmission of a predetermined amount of protective gas to said vessel. z

9. In an apparatus for treating articles with inflammable liquids, thecombination of a treatment vessel having means whereby it may be closedin an air-tight manner, or thrown open, means for supplying protectivegas to said vessel, a conduit for conveying an inflammable liquid intosaid vessel, a shut-off device controlling said conduit, a device forlocking said shut-off device, and a pressure member communicating withthe interior of said vessel and having lished in said vessel whichcauses said presan extension which normally prevents any release of saidlocking device until, by the initial introduction of a predeterminedamount of protective gas into said treatment vessel, a pressurecondition is estabsure, member extension to be actuated. to enable thelocking device to be unlocked, whereafter inflammable liquid may beintroduced into said vessel.

10. In an apparatus for treating articles with inflammable liquids, thecombination of a treatment vessel having means whereby it may be closedin an air-tight manner,

or thrown open, means for connecting said vessel with a protective gassupply, a conduit for supplying an inflammable liquid to said vessel, ashut-off device controlling said conduit, a device for locking in .itsclosed position, the shut-0E device controlling the flow'throughsaid'conduit, a gas receiver for storing protective gas of decreasedpressure discharged from said vessel, a connection between said gasreceiver and said vessel, a pressure member disconnectibly inserted intosaid connection, a device in said connection adapted in proper order todisconnect said pressure member, thereby opening a direct connectionwith said gas receiver, and toclose said connection entirely at a laterstage, a positive connection between said disconnecting and closingdevice and said locking device whereby both can be operated onlysimultaneously, and a pressure member extension which normally preventsany movement of said disconnecting and closing device until,

by the initial introduction of a predetermined amount of protective gasinto said treatment vessel, a pressure condition is established in saidvessel which causes said pressure member extension to be moved to enablesaid locking device to be unlocked, whereafter inflammable liquid may besupplied to said vessel;

11. In an apparatus for treating articles with inflammable liquids, thecombination pf a treatment vessel having means whereby it may be closedin an air-tight manner, or thrown open, meansfor supplying a protectivegas to said vessel, receptacles for inflammable liquids of variousdegrees of purity, conduits for conveying to said vessel, inflammableliquids of various degrees of purity, shut-ofl' devices in saidconduits, a device for normally locking said shut-ofi' devicessimultaneously in their closed position, a receiver for storingprotective gas discharged from said vessel, a connection between saidgas, receiver and said vessel, a pressure member disconnect- 'iblyinserted in the last-named connection,

adapted to prevent any movement of saidflow-changing and stopping deviceuntil a predetermined pressure condition is first established in saidvessel, which pressure condition insures the presence, during thetreatment of the articles, of a non-explosive mixture of gases andvapors, and causes the extension of said pressure member to come out ofcontact with said flow-changing and stopping device so as to release thesame, whereafter said flow-changing and stopping device may be operatedto unlock said locking device, thus enabling inflammable liquids tobesupplied to said vessel.

12. In an apparatus for treating articles with inflammable liquids, thecombination of a treatment vessel having means whereby it may be closedin an air-tight manner, or thrown open, means for initially supplying acertain amount of protective gas to said vessel, a receptacle adapted tocontain an inflammable liquid in a pure state, a connection forsupplying protective gas to said receptacle, a second receptacle,connected to the outlet of said treatment vessel and adapted to storefor further use, inflammable liquids which has been used in saidtreatment vessel, means for connecting said second receptacle with asource of protective gas, conduits for conveying inflammable liquidsfrom each of said receptacles to said treatment vessel, separateshut-01f devices for controlling the flow of the liquids through each ofsaid conduits, a single locking device for normally locking both of saidshut-off devices simultaneously in' their closed position, a gasreceiver and a connection thereto for storing protective gas dischargedfrom said treatment vessel, a third receptacle adapted to receive spentliquids discharged from said treatment vessel, a connection between saidthird receptacle and said gas receiver for supplying protective gas ofdiminished pressure to said third receptacle, a pressure memberdisconnectibly inserted in said connection between said treatment vesseland said gas receiver, a three-way ccck within the last-namedconnection, said cock being connected with said locking devicepositively in such a manner that both can be operated only together, anda safety latch on said pressure member, adapted to prevent any movementof said three-way cock until a predetermined pressure condition is firstestablished insaid vessel, which pressure condition insures thepresence, during the treatment of the articles, of a non-explosivemixture of gases and vapors, and. causes the safety latch of saidpressure member to come out of contact with said three-way cock so as torelease the same, whereafter said cock may be operated so as to unlocksaid locking device and to enable the inflammable liquids to be suppliedto said vessel.

13. In an apparatus for treating articles with inflammable liquids, thecombination of a treatment vessel having means whereby it may be closedin an air-tight manner, or thrown open, a connection for supplying aprotective gas to said vessel, means for opening and closing saidconnection, receptacles adapted to contain pure inflammable liquid andpartly soiled inflammable liquid respectively, separate connections forsupplying these receptacles with protective gas, an opening and closingdevice in the connection for supplying protective gas to the receptaclecontaining partly soiled liquid, a connection between this latterreceptacle and the outlet of said treatment vessel, means fortemporarily equalizing the pressures in the treatment vessel and in saidlast-named receptacle respectively, conduits for separately supplyinginflammable liquids from each of said rece tacles to said treatmentvessel, a shut-01f evice in each of said conduits, a locking device fornormally locking both of said shut-ofl' devices simultaneously, in theirclosed position, a gas receiver, a connection between said receiver andthe treatment vessel, a pressure member disconnectibly inserted in thelast-named connection, a three-way cock located in the same connectionand adapted to alternately disconnect said pressure member and to closesaid connection entirely, said three-way cock being connected positivelywith the aforesaid locking device in such a manner that both can beoperated only simultaneously, an extension on said pressure member fornormally locking said three-way cock until a predetermined-pressurecondition is established in said treatment vessel, which conditioncauses the pressure member to release said three-way cock,va hand crankrevoluble in one direction only, operative connections between this handcrank and the said three-way cock and the said opening andclosing meanswhich controls the supply of protective gas to said treatment vessel andto said receptacle containing partly soiled inflammable liquid, wherebysaid cock and said opening and closing means may be actuated in theproper succession from said hand crank on the release of said three-waycock, a receptacle for receiving spent liquid from said treatmentvessel, a connection between said receptacle and said gas receiver, andan exhausting device adapted to be connected temporarily with saidtreatment vessel.

In testimony whereof, I have hereunto set my hand in the presence of thesubscribing witnesses.

PAUL GUNGERICH.

Witnesses:

WQLDEMAR HAUPT, HENRY HAsPER:

